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Stony coral tissue loss disease (SCTLD) was first observed in September 2014 near Virginia Key, Florida. In roughly six years, the disease spread throughout Florida and into the greater Caribbean basin. The high prevalence of SCTLD and high resulting mortality in coral populations, and the large number of susceptible species affected, suggest that this outbreak is one of the most lethal ever recorded. The initial recognition and management response to this catastrophic disease in Florida was slow, which delayed the start of monitoring programs and prevented coordinated research programs by at least two years. The slow management response was a result of several factors that operated concurrently. First, the Port Miami dredging project was ongoing during the coral disease epidemic and dredging rather than SCTLD was blamed by some managers and local environmental groups for the extreme coral losses reported in the project’s compliance monitoring program. Second, this blame was amplified in the media because dredging projects are intuitively assumed to be bad for coral reefs. Third, during this same time State of Florida policy prohibited government employees to acknowledge global warming in their work. This was problematic because ocean warming is a proximal cause of many coral diseases. As a result, the well-known links between warming and coral disease were ignored. A consequence of this policy was that the dredging project provided an easy target to blame for the coral mortality noted in the monitoring program, despite convincing data that suggested otherwise. Specifically, results from the intensive compliance monitoring program, conducted by trained scientific divers, were clear. SCTLD that was killing massive numbers of corals throughout Florida was also killing corals at the dredge site – and in the same proportions and among the same suite of species. While eradication of the disease was never a possibility, early control measures may have slowed its spread or allowed for the rescue of significant numbers of large colonies of iconic species. This coral disease outbreak has similarities to the COVID-19 pandemic in the United States and there are lessons learned from both that will improve disease response outcomes in the future, to the benefit of coral reefs and human populations.

Significant population declines in Acropora cervicornis and A. palmata began in the 1970s and now exceed over 90%. The losses were caused by a combination of coral disease and bleaching, with possible contributions from other stressors, including pollution and predation. Reproduction in the wild by fragment regeneration and sexual recruitment is inadequate to offset population declines. Starting in 2007, the Coral Restoration Foundation™ evaluated the feasibility of outplanting A. cervicornis colonies to reefs in the Florida Keys to restore populations at sites where the species was previously abundant. Reported here are the results of 20 coral outplanting projects with each project defined as a cohort of colonies outplanted at the same time and location. Photogrammetric analysis and in situ monitoring (2007 to 2015) measured survivorship, growth, and condition of 2419 colonies. Survivorship was initially high but generally decreased after two years. Survivorship among projects based on colony counts ranged from 4% to 89% for seven cohorts monitored at least five years. Weibull survival models were used to estimate survivorship beyond the duration of the projects and ranged from approximately 0% to over 35% after five years and 0% to 10% after seven years. Growth rate averaged 10 cm/year during the first two years then plateaued in subsequent years. After four years, approximately one-third of surviving colonies were ≥ 50 cm in maximum diameter. Projects used three to sixteen different genotypes and significant differences did not occur in survivorship, condition, or growth. Restoration times for three reefs were calculated based on NOAA Recovery Plan (NRP) metrics (colony abundance and size) and the findings from projects reported here. Results support NRP conclusions that reducing stressors is required before significant population growth and recovery will occur. Until then, outplanting protects against local extinction and helps to maintain genetic diversity in the wild.